Otitis media/interna and encephalitozoonosis are the most common causes of head tilt in pet rabbits in the UK: 73 cases (2009‒2020).

BACKGROUND: There are limited studies that identify diseases associated with head tilt in pet rabbits. METHODS: This was an observational, retrospective, single-centre study of rabbits with head tilt presented between 2009 and 2020. Descriptive statistics were performed for all cases, whereas univariate and multivariate analyses were only performed for the 36 cases with a final diagnosis. RESULTS: Seventy-three rabbits met the inclusion criteria. The final diagnoses included Encephalitozoon cuniculi meningoencephalomyelitis (EC) (15/36; 41.7%), otitis media/interna (OMI) (8/36; 22.2%) and concurrent EC and OMI (13/38; 36.1%). Subacute-to-chronic onset was more common in rabbits with OMI than in those with EC (p = 0.018). Previous middle ear surgery (p = 0.046) and a diagnosis of otitis externa (p = 0.004) significantly increased the risk of OMI. Meloxicam was associated with improvement of clinical signs (p = 0.007). Upright ears (p = 0.013), recumbency (p = 0.037) and impaired mentation (p = 0.001) were associated with a higher risk of death/euthanasia. The proportions of residual head tilt (66.7%) and relapse of vestibular signs (42.1%) were high. LIMITATIONS: This was a retrospective study with cases varying in their investigation and conclusive final diagnoses. CONCLUSION: OMI and EC were the most common aetiologies of head tilt in pet rabbits in the UK. Meloxicam might be associated with a favourable outcome in affected rabbits. Paired EC serology and a CT scan of the head should be the baseline investigation for head tilt in rabbits.

Episodic mandibular tremor in dogs: an idiopathic movement disorder or a manifestation of pain.

OBJECTIVE: Episodic mandibular tremor (EMT), manifested as teeth chattering, is not well described in dogs. The aim of this study was to describe clinical signs, MRI findings, and outcome of dogs with EMT. ANIMALS: 11 dogs retrospectively and 31 dogs in an online survey. METHODS: A retrospective multicenter study of dogs with EMT between 2018 and 2023 and prospective online questionnaire open to owners of pets with teeth chattering. RESULTS: All dogs had rapid and short-lasting (< 1 minute) episodes of EMT in the absence of other neurological signs. Lip smacking occasionally accompanied the tremor in 5 of 11 (45.5%) hospital dog cases. Excitement was a common trigger in 14 of 31 (45.2%) dogs from the survey. Cavalier King Charles Spaniel was the most common breed in both clinical and survey populations. Median age at presentation was 3 years for both hospital cases and the survey dogs. A concurrent medical condition was present in 8 of 11 (72.7%) hospital cases and 20 of 31 (64.5%) survey dogs. In 3 hospital dogs that underwent further investigations, no brain disease was present. CLINICAL RELEVANCE: EMT and its clinical features are presented for the first time, shedding light on a clinical sign that might resemble an idiopathic movement disorder or a manifestation of pain in dogs.

Cytological evaluation, culture and genomics to evaluate the microbiome in healthy rabbit external ear canals.

BACKGROUND: Lop-eared rabbits may be predisposed to otitis externa (OE) as a consequence of their ear conformation. Although otoscopy, otic cytological evaluation and culture are valuable tools in dogs and cats, published data on rabbits remain lacking. HYPOTHESIS/OBJECTIVES: This study aimed to assess the utility of otoscopy and cytological results in evaluating healthy rabbit external ear canals (EECs) and to characterise ear cytological and microbiological findings through culture techniques and metagenomic sequencing. ANIMALS: Sixty-three otitis-free client-owned rabbits. MATERIALS AND METHODS: All rabbits underwent otoscopy and ear cytological evaluation. In a subset of 12 rabbits, further bacterial and fungal culture, fungal DNA assessment and metagenomic sequencing were performed. RESULTS: Otic cytological results revealed yeast in 73%, cocci in 42.9% and rods in 28.6% of healthy rabbit EECs. Compared to upright-eared rabbits, lop-eared rabbits had more discharge and more bacteria per oil immersion field. Culture isolated eight different species yet metagenomic sequencing identified 36, belonging to the Bacillota (Firmicutes), Pseudomonadota and Actinomycetota phyla. Staphylococcus were the most commonly observed species with both methods. Ten of 12 rabbits were yeast-positive on cytological evaluation with only three yielding fungal growth identified as Yarrowia (Candida) lipolytica, Eurotium echinulatum and Cystofilobasidium infirmominiatum. CONCLUSIONS AND CLINICAL RELEVANCE: Healthy rabbit EECs lack inflammatory cells yet can host yeast and bacteria, emphasising the need to evaluate cytological results alongside the clinical signs. Lop-ear anatomy may predispose to bacterial overgrowth and OE. Notably, yeasts may be present despite a negative culture.

First case report of cutaneous sporotrichosis (Sporothrix species) in a cat in the UK.

CASE SUMMARY: A 12-year-old female neutered indoor-outdoor domestic longhair cat presented with frequent sneezing and a nodular, suppurative lesion on its dorsal nose. Histopathological examination revealed a fungal granuloma. PCR and sequencing of the ribosomal internal transcribed spacers (ITS) regions (ITS-F and ITS-R) confirmed an infection with a Sporothrix species. Further sequencing of the beta-tubulin and calmodulin genes confirmed Sporothrix humicola, which lies within the Sporothrix pallida complex. The cat had concurrent diabetes mellitus, which responded to insulin therapy and diet. Oral itraconazole at 10 mg/kg PO q24h resulted in resolution of the lesions after 12 months. Treatment was well tolerated. RELEVANCE AND NOVEL INFORMATION: This is the first report of sporotrichosis in a cat in the UK and only the fifth worldwide involving the S pallida complex. Clinicians, pathologists and microbiologists need to be aware of the potential of Sporothrix infections in the UK and the ability of S pallida complex to cause opportunistic infections. Molecular techniques can achieve rapid and accurate identification of rare fungal organisms. A precise diagnosis with molecular testing can provide information regarding prognosis, treatment and zoonotic implications.